Erva-mate e atividade antioxidante

• Ano de defesa: 2005
• Autor(a) principal: Canterle, Liana Pedrolo
• Tipo de documento: Dissertação
• Tipo de acesso: Acesso aberto
• Idioma: por
• Instituição de defesa: Universidade Federal de Santa Maria; BR; Ciência e Tecnologia dos Alimentos; UFSM; Programa de Pós-Graduação em Ciência e Tecnologia dos Alimentos
• Palavras-chave em Português: Ilex paraguariensis; Atividade antioxidante; Ensaio biológico; Ensaio químico; Antioxidant activity; Biological assay; Chemical assay; CNPQ::CIENCIAS AGRARIAS::CIENCIA E TECNOLOGIA DE ALIMENTOS
• Link de acesso: http://repositorio.ufsm.br/handle/1/5805

Ilex paraguariensis Saint Hilaire (Aquifoliaceae), popularly known as yerba-mate, is a native species of South America and has its area of natural occurrence restricted to Brazil, Paraguay and Argentina. It is a product that still has a lot to be improved, mainly, in terms of its industrial uses, in international level. Antioxidants are composts that work as blockers of the oxide-reducers processes unchained by the free radicals, impeding the damages generated by them, being widely used in food, medicines and cosmetics, and recently, they are also being used in antioxidant therapies in diseases where free radicals are implicated. This work has as objective to evaluate the antioxidant capacity of the product yerba-mate chimarrão type, using samples of the RS and SC, in the months june, july and august, through biological and chemical assays. The biological study was accomplished in eucariotics cells of the yeast Saccharomyces cerevisiae treated with yerba-mate samples in presence of the apomorphine and paraquat dichloride agents during the aerobic metabolism (cellular multiplication). The obtained results indicate that the antioxidant capacity of the samples varies significantly in function of the type and concentration of the stressor agents, the concentrations of the samples, the mate type (native or cultivated) and of the producer state (RS and SC). Between the states, RS state presented higher antioxidant effect in vivo, where reforested mate were more efficient as cellular protectors, the opposite happened in SC state. The chemical evaluation was based on the determination of the Total Antioxidant Activity (Hydrophilic and Lipophilic), where the capacity of the sample in to sequestrate the ABTS radical, the Reducing Power, where the iron ion produced in the redox reaction forms a colored product when it reacts with the DPPH radical, with maximum absorption to 525 nm, the 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical sequestrating effect, based on the capacity of the antioxidant in donating hydrogen for the DPPH radical provoking the sweeping of it of the middle of reaction, modifying the color of the solution were verified. The found values in the analyses in vitro show that the antioxidant capacity in the majority of the samples varied significantly in function of the producer state and of the mate type in the three months of analysis (June, July and August). Hydrophilic Antioxidant Activity was higher in August for all the samples, varying between 0,1336-0,5627 mM equivalent of Trolox, for Lipophilic there was a higher variation among the months of analysis, with the values being between 4,9516-27,6685 mM equivalent of Trolox. For the other chemical analyses, all the samples showed higher antioxidant activity in June, among 4,4373-12,4082 mM equivalent of quercetin to Reducer Power and 4,0221-11,1393 mM equivalent of Trolox the 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical sequestrating effect. The results were obtained through the construction of standard curves, treated statisticlly through variance analysis (ANOVA) and Tukey´s post test using Microsoft Excel software. All tests were performed in triplicate. It was concluded that the yerba-mate, ingested in chimarrão form, really has a great antioxidant effect when compared to other natural products with already proven action, in chemical and biological systems, and that this property can be explored seeking the diversification in the consumption ways, fact that would facilitate the expansion of the culture in the country.